On a darker note, since no one knows Bob is a hero, on his second attempt Emperor Evulz simply has a mook gun Bob down in the street. Everyone assumes it's just a random murder, and Emperor Evulz is able to repeat the same plan as before in total secrecy.
Defied: Bob's companions realize nobody knows what he did for the people, so they head out and spread the story far and wide so Bob will be remembered.
Implied: After Bob saves the world, the story ends, and there are no clues that the events become known by everyone or not, but looks like they weren't.
Making this story a secret was a terrible idea, because when Emperor Evulz is back, the world's authorities have a hard time defeating him but they could defeat him easier if the events of his first defeat were known.
Also, since Bob forgets what happened, he thinks he is normal and doesn't go back to fight him again.
Reconstructed: Don't worry, his first defeat it was a secret, but his second defeat it's not, and Bob fights him again.
Played For Laughs: Bob wanted so much to be a famous and respected hero, but since no one knows of his adventure, he goes back to be a loser that everyone picks on.
Played For Drama: Bob wanted so much to be a famous and respected hero, but since no one else knows of his adventure, he becomes very depressed.